// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// This file contains unit tests for gles2 commmands

#include <limits>

#include "base/bind.h"
#include "base/location.h"
#include "base/single_thread_task_runner.h"
#include "base/synchronization/waitable_event.h"
#include "base/threading/thread.h"
#include "gpu/command_buffer/common/gles2_cmd_format.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace gpu {
namespace gles2 {

    class GLES2FormatTest : public testing::Test {
    protected:
        static const unsigned char kInitialValue = 0xBD;

        void SetUp() override { memset(buffer_, kInitialValue, sizeof(buffer_)); }

        void TearDown() override { }

        template <typename T>
        T* GetBufferAs()
        {
            return static_cast<T*>(static_cast<void*>(&buffer_));
        }

        void CheckBytesWritten(
            const void* end, size_t expected_size, size_t written_size)
        {
            size_t actual_size = static_cast<const unsigned char*>(end) - GetBufferAs<const unsigned char>();
            EXPECT_LT(actual_size, sizeof(buffer_));
            EXPECT_GT(actual_size, 0u);
            EXPECT_EQ(expected_size, actual_size);
            EXPECT_EQ(kInitialValue, buffer_[written_size]);
            EXPECT_NE(kInitialValue, buffer_[written_size - 1]);
        }

        void CheckBytesWrittenMatchesExpectedSize(
            const void* end, size_t expected_size)
        {
            CheckBytesWritten(end, expected_size, expected_size);
        }

    private:
        unsigned char buffer_[1024];
    };

    void SignalCompletion(uint32* assigned_async_token_ptr,
        uint32 async_token,
        AsyncUploadSync* sync)
    {
        EXPECT_EQ(async_token, *assigned_async_token_ptr);
        sync->SetAsyncUploadToken(async_token);
    }

    TEST(GLES2FormatAsyncUploadSyncTest, AsyncUploadSync)
    {
        const size_t kSize = 10;
        const size_t kCount = 1000;

        base::Thread thread("GLES2FormatUploadSyncTest - Fake Upload Thread");
        thread.Start();

        // Run the same test 50 times so we retest the wrap as well.
        for (size_t test_run = 0; test_run < 50; ++test_run) {
            AsyncUploadSync sync;
            sync.Reset();

            uint32 buffer_tokens[kSize];
            memset(buffer_tokens, 0, sizeof(buffer_tokens));

            // Start with a token large enough so that we'll wrap.
            uint32 async_token = std::numeric_limits<uint32>::max() - kCount / 2;

            // Set initial async token.
            sync.SetAsyncUploadToken(async_token);

            for (size_t i = 0; i < kCount; ++i) {
                size_t buffer = i % kSize;

                // Loop until previous async token has passed if any was set.
                while (buffer_tokens[buffer] && !sync.HasAsyncUploadTokenPassed(buffer_tokens[buffer]))
                    base::PlatformThread::YieldCurrentThread();

                // Next token, skip 0.
                async_token++;
                if (async_token == 0)
                    async_token++;

                // Set the buffer's associated token.
                buffer_tokens[buffer] = async_token;

                // Set the async upload token on the fake upload thread and assert that
                // the associated buffer still has the given token.
                thread.task_runner()->PostTask(
                    FROM_HERE, base::Bind(&SignalCompletion, &buffer_tokens[buffer], async_token, &sync));
            }

            // Flush the thread message loop before starting again.
            base::WaitableEvent waitable(false, false);
            thread.task_runner()->PostTask(
                FROM_HERE,
                base::Bind(&base::WaitableEvent::Signal, base::Unretained(&waitable)));
            waitable.Wait();
        }
    }

// GCC requires these declarations, but MSVC requires they not be present
#ifndef _MSC_VER
    const unsigned char GLES2FormatTest::kInitialValue;
#endif

#include "gpu/command_buffer/common/gles2_cmd_format_test_autogen.h"

} // namespace gles2
} // namespace gpu
